This pattern indicates that an action has just been completed from the speaker's subjective viewpoint, meaning 'just did...'. The emphasis is on the recency of the action, even if some objective time has passed. For example: 彼は日本に来たばかりなので、まだ日本語が話せません。(He just came to Japan, so he can't speak Japanese yet.)

ある行為が終わったばかりであること、その直後であることを主観的に表す。例：日本に来たばかりだ。